Allow one-copy task tile worker pool to use compressed textures.

cc/resources/resource_pool.cc

Index: cc/resources/resource_pool.cc
diff --git a/cc/resources/resource_pool.cc b/cc/resources/resource_pool.cc
index 835c37d6c32d9f23029bcfea419ad6f8f2b3f2fc..a94d46e8878578842d0ef6f6c2116d4ae5e2f8e0 100644
--- a/cc/resources/resource_pool.cc
+++ b/cc/resources/resource_pool.cc
@@ -89,8 +89,16 @@ ResourcePool::~ResourcePool() {
   DCHECK_EQ(0u, total_resource_count_);
 }
 
-Resource* ResourcePool::AcquireResource(const gfx::Size& size,
+Resource* ResourcePool::AcquireResource(const gfx::Size& desired_size,

[reveman, 2015/09/30 09:55:15]

Can we instead just make sure resource dimensions are always multiple of 4 and
have a DCHECK here independent of format? It doesn't make sense for us to ever
use a different resource size as that can easily result in worse performance as
the starting address of each row might not be 8 byte aligned.

[christiank, 2015/11/26 15:35:35]

I guess that makes sense. I am not sure if there are specific use cases for
other sizes now that I think about it. I can vaguely recall something about
video elements or WebGL introducing a layer with an odd size.

Do you have any hints on where I can look to restrict the resource size?

[reveman, 2015/11/27 16:46:49]

https://code.google.com/p/chromium/codesearch#chromium/src/cc/layers/picture_...

[christiank, 2015/11/30 15:41:08]

Perfect, thanks! Will look at this tomorrow.

[christiank, 2015/12/01 15:01:07]

Should now be fixed.

                                         ResourceFormat format) {
+  gfx::Size size = desired_size;
+  if (IsResourceFormatCompressed(format) &&
+      (size.width() % 4 != 0 || size.height() % 4 != 0)) {
+    // Round the size up to the nearest multiple of four.
+    size.SetSize(4 * std::ceil(static_cast<float>(size.width()) / 4),
+                 4 * std::ceil(static_cast<float>(size.height()) / 4));
+  }
+
   for (ResourceDeque::iterator it = unused_resources_.begin();
        it != unused_resources_.end(); ++it) {
     ScopedResource* resource = *it;